Evaluation of the use of biomass as a source of energy for industrial processes. A selected case in the Portuguese scenario

Abstract: Switching from fossil fuels to biofuels has already been proven to be a good business for some industries such as the pulp industry and the wood industry in general, but very limited experience exists about the profitability of this change in other industrial contexts. This thesis investigates the financial viability of a partial shift to a biomass based energy system for the structural ceramics sector in Portugal. Specifically the financial performance in terms of Net Present Value and Simple Payback Period for the substitution of different fossil fuels for the drying phase of the production process has been investigated under different combinations of fossil fuels prices and CO2 allowance prices. Two different technological scenarios have been tested. The first one foresees the combined production of heat and power, while the second one is a heat only technological scenario. In the CHP scenario the substitution of all the fuels considered for analysis is feasible and in most of the cases very remunerative, due to the high prices paid for the green electricity produced and sold to the grid. In the heat only scenario instead, the results show that substitution of fuel oil and natural gas with biomass residues is already profitable under the current scenario, while the substitution of petroleum coke is practically never feasible when a heat only system is tested.